What we think of as tumbleweeds are actually Russian thistle, and they first showed up in the US in a shipment of flax-seed that was sent to South Dakota. A few years later, they were found all over the West, from California and North into Canada.
Single plants can get
as large as a small car and bear up to 250,000 seeds at once,
making the invasive species a massive problem that was already
getting the attention of the US Department of Agriculture in
Since tumbleweeds can
thrive with little water, they were capable of taking over towns
and driving people from their homes as they spread across the
wide expanse of the West.